Conveying system and valve construction therefor



M. J. BOZICH Dec. 21, 1965 4 Sheets-Sheet 1 Original Filed Feb. 28, 1962I NVENTOR. mzcwaal. J. .BQZICH'.

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CONVEYING SYSTEM AND VALVE CONSTRUCTION THEREFOR Original Filed Feb. 28,1962 4 Sheets-Sheet 2 INVENTOR. (710/954 Bozxefl '1'; a rrozMs Y Dec.21, 1965 Original Filed Feb. 28, 1962 4 Sheets-Sheet 3 54 f 64 :3 P8 65L 46 ww 6' I L x mm n filfi 55 1 I NVENTOR. mzcmvcz. J. 5021:!

M- J. BOZlCH Dec. 21, 1965 CONVEYING SYSTEM AND VALVE CONSTRUCTIONTHEREFOR Original Filed Feb. 28, 1962 4 Sheets-Sheet 4 JONPPZOU N952 nmm? 3mm mfim 3E0 81 a on @507 INVENTOR. (VIC/1:964 J. Bozrcvl.

=5 7'7'a 4EJ/ Y United States Patent 3,224,812 CONVEYING SYSTEM ANDVALVE CONSTRUCTIQN THEREFOR Michael J. Eozich, 1059 Bay Ridge Ave.,Pittsburgh, Pa. Original application Feb. 28, 1962, Ser. No. 176,234,now

Patent No. 3,185,434, dated May 25, 1365. Divided and this applicationApr. 13, 1965, Ser. No. 449,121

9 Claims. (Cl. 30228) This is a division of my copending applicationSerial Number 176,234, filed February 28, 1962, now Patent No.3,185,434, dated May 25, 1965.

This invention relates to pneumatic conveying systems for granularmaterial and the like, and more particularly to a diverting valve for apneumatic conveying system which is usable for selectively directing aflow of material conveyed through a main conduit into a branch conduitleading to a storage bin or the like.

In systems for conveying solid materials such as granular ingredientswhich are highly abrasive, it is necessary to maintain the conveyingsystem as streamlined as possible in order to reduce the efifects ofabrasion on the conveying system in general and the valve structures forcontrolling discharge in particular. Furthermore, it is also importantto provide a number of different outlets so that the material beingconveyed can be discharged at any one of several different locations.For example, these locations can be a series of bins for storage,reaction chambers, tank cars, trucks or the like.

It is an object of the present invention to provide a conveying systemin which solid material can be transmitted under pneumatic pressure orthe like and can be discharged into any one of several differentlocations by means of a novel system of interrelated diverting valvemeans.

A further object of the invention is to provide a novel control systemwhich prevents the possibility of discharging material into the wronglocation, this being accomplished by means of a novel control systemcombined with the valve arrangement.

A further object of the invention is to provide a diverting valve systemin which the main flow of material is opposed at the point of dischargeby a gaseous flow which is equal in pressure to the main flow and isprovided in volume sufficient to effect adequate diversion, the specificrate of flow of the opposing gas being selected in accordance with thematerial and abrasive qualities thereof which are being discharged.

A novel feature of the invention is that regardless of the number ofvalves, diverting air is used at the point of discharge of only onevalve so that its quantity will not change regardless of the number ofvalves in the conveying system.

Other objects and features of the invention will become apparent from aconsideration of the following description which proceeds with referenceto the accompanying drawings, wherein:

FIGURE 1 is a schematic view of a conveying system having a maindistribution conduit and four outlets each having an associateddiverting valve so that the material within the conduit can bedischarged through a preselected one of the outlets, the outlets in thiscase being storage bins;

FIG. 2 is an enlarged side elevational view of the diverting valvearrangement of the invention showing the enclosure which houses thevalve, the valve itself being shown in its closed and open positionswithin the enclosure by broken lines;

FIG. 3 is a sectional view taken substantially along line IIIIII of FIG.2;

FIG. 4 is a detailed view of the valve construction and support armtherefor;

3,224,812 Patented Dec. 21, 1965 FIG. 5 is a cross-sectional view takenalong line V-V of FIG. 4;

FIG. 6 is a schematic illustration of the action of a secondary airsource in diverting finely divided material through the valve of theinvention; and

FIG. 7 is a schematic wiring diagram illustrating how the divertingvalves are electrically interconnected to prevent accidental dischargeof the material through the wrong discharge opening.

Referring now to the drawings, and specifically to FIG. 1, there isprovided a pneumatic conveying conduit 10 of steel or the like which issuitable for conducting the conveyed material, such as crushedpulverulent material, along the length of the conduit under the actionof pneumatic pressure. The material passes continuously through theconduit at a rate and pressure suflicient to carry the conveyed materialtherewith. The material flows at a rather high velocity, as for example5,000-8,000 lineal feet per minute and has an abrasive etfect upon theconduit which dictates as nearly a streamlined construction as possible.

At spaced intervals along the length of the conduit are valve assembliesdesigned generally by reference letters A, B, C and D, all of which areof substantially the same construction and serve to selectively divertthe flow of material within the distributing conduit into storage bins22, 24, 26 and 28. Although only four valves are shown herein, there isno practical limitation on the number of diverting valve mechanism whichcan be provided along the length of the conduit since the valves are nota source of pressure loss nor do they present any substantialobstruction to flow. In other words, the valves do not require anysubstantial increase in pressure for the primary air flow.

The diverting valves are usable not only for directing the flow ofmaterial into storage bins, but can also be used for channeling thematerial into reaction chambers, other conveying systems, or the like.It is a characteristic of each of the valve assemblies that itsconstruction is streamlined so as not to obstruct the passage ofmaterial in the conduit and to prevent wear under the action of theconveyed material passing the valve to a succeeding valve which might beopen.

Referring now to FIGS. 2 and 3, each valve is housed within a boxsection casing 32 having end walls 34 and 36 including openings 33 and35 through which the pneumatic conduit 10 passes, and side walls 38 and33 which provide a supporting surface for valve and valve actuator. Theportion of the conduit 10 within box assembly 32 is provided with adischarge opening 40 forming in its lower side a discharge openingthrough which material conveyed within conduit 10 is discharged into thebox assembly 32. As shown, the box assembly 32 has an open bottomprovided with a flange 31 which, in turn, is connected to the peripheryof a conduit 22, 24, 26 or 28 (FIG. 1) leading to an associated storagebin or the like, or to an opening in the storage bin itself. The opening40 is covered by an appropriate gasket 42 (FIGS. 3 and 4) which forms apneumatic seal around the edges of opening 40 to prevent any of theconveyed material from leaving the conduit 10 and also to prevent anypressure drop of the primary pneumatic pressure.

The gasket 42 has a similarly shaped backing 44 which reinforces theresilient gasket 42 and holds it against the surface of the conduit 10surrounding the elliptical opening 40. The combination of seal 42 andbacking 44 constitutes the functional portion of the valve, and isreferred to as a flap valve 45. The flap valve 45 is carried by asupport arm 46 which, as best shown in FIGS. 4 and 5, comprises spacedbars 48 and 50 sandwiched between bars 52 and 54 to provide an opening55 for the reception of an eyebolt 58, the eyebolt being held inposition by means of a bolt 59. The valve support arm is apertured at 62to receive a shaft 64 which is journaled at its opposite ends inbearings 65 and 67 (FIG. 3) carried on wall 38 and 39 of the casing 32.The backing 44 and gasket 42 are carried on the eyebolt 58 as shown inFIG. 4 such that the entire assembly can be adjustably rotated about theaxis of the bolt 59 by turning the adjusting bolts 60 and 61 which arethreaded into, and extend through, the support arm 46. As will beunderstood, the combination of eyebolt 58 and the bolts 60 and 61provide a means for adjusting the position of the backing 44 so that thesealing portion or gasket 42 is urged snugly against the conduit toeffect a tight sealing pressure therewith.

Projecting outwardly from one side of the support arm 46 is a bar 69which, when the support arm is disposed vertically as shown in dottedline position in FIG. 3, engages a cam 66 to effect rotation of theswitch arm 68 and thereby actuate limit switch 70. When the arm 46 is inits normal horizontally disposed position, as shown in full lines inFIG. 3, an arm 72 on the backing 44 engages cam 74 to rotate switch arm75 and actuate limit switch 76. As will be seen, these two limitswitches 70 and 76 are related so that the operation of the valveassembly will not divert a flow of the material being conveyed withinthe conduit 10 to the wrong location. The valve is operated between aclosed horizontal position and vertical open position by means of theshaft 64 which is driven by a sprocket wheel 78 having a drive chain connection 80 with a sprocket wheel 82, this latter sprocket being drivenby motor 84 through a gear reducer 86 mounted on top of the casing 32.

The material is fed into the conduit 10 by apparatus of the general typeshown in US. Patent No. 2,565,946 or copending application Serial No.120,719, filed June 29, 1961, now Patent No. 3,115,369, dated Dec. 24,1963. As shown in FIG. 1, such apparatus consists of a pair of hoppers90 and 92 arranged vertically one above the other. Only the lowerportion of the upper hopper 90 is shown, it being understood that thishopper is provided with an open top to permit granular or powderedmaterial to be poured therein. The lower hopper 92, designated as adelivery hopper, is provided with a funnel-shaped bottom 94 having anopening 96 leading into a T-section pipe 98 which, at its right-hand endis connected to the conveying conduit 10 that convey material to thevalves A-D. The left end of the T-section pipe 98 is connected, asshown, to a blower 100 of any standard construction, the power for suchblower being supplied by an electric motor 102.

Interconnecting the hoppers 90 and 92 is a section 104 having a flap 106therein which is pivotally connected to section 104 as at 108. Undernormal conditions, the flap 106 will rotate downwardly about pivot point108 to permit the material from hopper 90 to flow into hopper 92. When,however, an air blast is introduced into section 104 through conduit110, air pressure will build up above the material in hopper 92 torotate the flap 106 upwardly into the position shown such that it willblock off the passageway between hoppers 90 and 92 and shut oflt thesupply of material to hopper 92. Air under pressure may be supplied tosection 104 to rotate the flap 106 upwardly by means of a valve 112 inthe conduit 10, the arrangement being such that when valve 112 is openair under pressure will be supplied to section 104 from the blower 100.At the end of conduit 10 opposite the blower 100 is a second, smallerblower 114 which is driven by means of motor 116. As will be seen, theblower 114 provides a pressure which opposes that produced by blower100, this second source of air serving to divert material being conveyedfrom the main conduit 10 and through any one of the valves AD which isopen into its associated storage bin 22-28.

It will be understood by reference to FIGS. 2 and 3 that when any valveis closed with the gasket 42 in sealing engagement with the opening 40,granular or the like material in conduit 10 will pass over the opening40 and onto a succeeding valve. However, when the valve is open (i.e.,the dotted line position shown in FIGS. 3 and 4), material will continuethrough the valve to a point directly above the opening 44. At thispoint, the pressure from blower 114 will stop the movement of both theconveyed material and the primary air from blower which accomplishes thepneumatic conveying; and with the valve open and the opening 44 beingthe line of least resistance, the entire mass of material and air willfall downwardly through the valve opening 44 and into a storage bin orthe like. For the successful operation of the valve, air of sufficientquantity and pressure is required to do the actual diverting. Thisaction is best illustrated in FIG. 6. In this respect, the pressure ofthe secondary air from blower 114 must be equal to the pressure of theprimary air from blower 100 and the material conveyed thereby. Thevolume of secondary air, however, can be varied and this depends uponthe requirements of the particular conveying system. Tests have shownthat diverting can be accomplished with volumes as low as 10% of theconveying air and up to 100% or equal to the conveying air. These rateswill vary according to the material to be conveyed and the abrasivequalities of this same material.

It will be appreciated that all valves except the one leading to thedesired storage bin must be closed for the successful operation of thesystem. In this respect, air for diverting is required only at the oneparticular valve which is open such that the pressure of the secondaryair from blower 114 and its quantity will not change no matter how manyvalves are in the main conveying line 10.

It is characteristic of granular material transported under highpneumatic pressure to have an abrasive effect on the conduit and otheroperating portions of the system which are exposed to the flow ofmaterial. Since each of the valves, when closed, is of streamlinedcontour along the interior of the conduit, the abrasive effect issubstantially reduced, thereby minimizing the principal source of wearin the system. At the same time, this streamlined effect also preventsappreciable pressure drops which detract from the efiiciency of thesystem. There is no practical limitation in the number of outlets whichcan be provided in this system. Four outlets are specifically shown butthis can be increased to ten, fifteen or any other number. There is nolimitation on the class of material being transported other than that itmust be capable of flow movement under pneumatic force.

As was mentioned above, the successful operation of the system shown inFIG. 1 depends upon only one of the valves AD being open While theothers are closed. The limit switches 70 and 76 on each valve, whenproperly placed and electrically interconnected will assure that if thevalves are not in their desired positions the system will not start,thereby eliminating the possibility of discharging material into thewrong storage bin.

One illustrative type of electrical control system for achieving theforegoing is shown in FIG. 7 wherein the control circuits for the valvesA, B and C only are shown, it being understood that this may be extendedto any desired number. With reference to FIG. 7, it will be noted that arelay A, 120B or 120C is provided for each of the valves. In the case ofvalve B, the arm 46B is shown in its downwardly extending or openposition; whereas in the case of valves A and C the arms 46A and 46C areshown in their closed positions. With the arm 4613 in the open position,it will engage the limit switch 70B to open its normally closed contacts122B while closing its normally open contacts 1243. At this time, thelimit switch 76B will be in a position where its contacts 126B are openwhile contacts 12813 are closed.

Let us assume, for example, that it is desired to discharge materialinto the storage bin beneath valve B. Under these circumstances, thepush button identified start B will be depressed, thereby momentarilyenergizing the coil on relay 120B. When relay 120B is energized, itscontacts 130B pull in or close to provide a holding circuit for the coilon relay 120B through the normally closed stop push button identified asstop B. When the start B button is initially depressed, the arm 46B willbe rotated upwardly from the position shown in FIG. 6 wherein contacts126B are closed and contacts 1283 are open on limit switch 76B. Inaddition, contacts 124B on limit switch 70B will be open while contacts122B will be closed. Consequently, when the start B button is depressedand relay 120B energized, contacts 132B close as shown to complete acircuit through contacts 1228, which are now closed, to one winding 134Bon direct current motor 84B. This causes the motor to drive the shaft64B and rotate the arm 463 in a counterclockwise direction as viewed inFIG. 7. This rotation of the arm 46B will continue until it strikes thelimit switch 70B to open contacts 122B, whereupon the circuit to motor84B is broken and the motor stops.

The motors 102 and 116 for blowers 100 and 114, respectively, arecontrolled by a motor control circuit 136. This control circuit will beactuated to start the motors 102 and 116 when start switch 138 is closedand when only one of the valves A, B or C is open while the other valvesare closed. Thus, the motor control circuit 136 will be actuated throughswitch 138, lead 140, contacts 126C on limit switch 76C which are nowclosed since the arm 46C is raised, lead 142, contacts 12413 on limitswitch 70B which are now closed since arm 46B is now lowered with thevalve open, contacts 144B on relay 120B which are now closed since therelay is energized, lead 146 and contacts 126A on limit switch 76A. Inthis manner, it can be seen that the motors 102 and 116 will start toinitiate the conveying operation after start B push button is depressedwhen, and only when, the valve B is in its open position while the othervalves are all closed. That is, if either of the contacts 126A or 126Cis open indicating that its associated valve is open, the circuit cannotbe completed to control circuit 136 to start the motors. Thus, thesystem eliminates the possibility of discharging material into the wrongstorage bin.

When it is desired to close the valve B, the push button identified asstop B will be depressed, thereby breaking the holding circuit for thecoil on relay 120B and deenergizing this relay. When the relay 120Bdeenergizes, the circuit to the motor control circuit 136 is brokenthrough contacts 1328 on relay 120B so that the motors 102 and 116 stop.At the same time, the contacts 148B on relay 1203 will not close toenergize the other winding 150B on motor 84B through contacts 128B onlimit switch 176B which are now closed since the arm 46B is in itsdownwardly-extending position. Consequently, the motor 84B will nowrotate in the opposite direction to rotate the arm 46B in a clockwisedirection as viewed in FIG. 6 until the limit switch 76B is engaged toclose contacts 126B and open contacts 128B, whereupon the motor 84Bstops preparatory of a succeeding cycle of openat-ion. In the particularcircuit shown therein, it is, of course, necessary to open switch 138before all of the limit switches 76A, 76B and 76C are engaged by theirassociated arms to prevent the motors 102 and 116 from operating whenall valves are closed. As will be understood, this may be accomplishedautomatically, the circuit shown herein being for illustrative purposesonly.

Although the invention has been shown in connection with a certainspecific embodiment, it will be readily apparent to those skilled in theart that various changes in form and arrangement of parts may be made tosuit requirements without departing from the spirit and scope of theinvention.

I claim as my invention:

1. In a system for pneumatically conveying finely divided materials, thecombination of a pneumatic conveying conduit, a device for forcing astream of air into one end of the conduit to move finely dividedmaterial therealong, an opening in the wall of said conduit, cover meansfor said opening having a first position wherein it covers the openingand a second position wherein it uncovers the opening to permit granularmaterial to pass therethrough, and means on the side of the openingopposite said one end of the conduit for creating a flow of air opposingthat created by said device whereby the opposing flow of air will stopboth the flow of air from said device and the granular material carriedthereby adjacent the opening and cause the granular material to passthrough said opening.

2. The combination of claim 1 wherein the pressure of the opposing flowof air is substantially equal to the pressure of the flow of air fromsaid device.

3. The combination of claim 1 wherein the opposing ilow of airsubstantially equal in pressure to the flow of air from said device andwherein the volume of the opposing flow of air is in the range of 10% toof the volume of the flow of air from said device.

4. In a system for pneumatically conveying finely divided materials, thecombination of a pneumatic c0nveying conduit, a device for forcing astream of air into one end of the conduit to move finely dividedmaterial therealong, an opening in the bottom of said conduit, covermeans for said opening having a first position wherein it covers theopening and a second position wherein it uncovers the opening to permitgranular material to drop therethrough, and means on the side of theopening opposite said one end of the conduit for creating a flow of airopposing that created by said device whereby the opposing -flow of airwill stop both the flow of air from said device and the material carriedthereby over said opening and cause the granular material to fallthrough the opening.

5. The combination of claim 4 wherein the area of said opening is largerthan the cross-sectional area of the conveying conduit such that whenair and material pass out of the opening their velocity will be loweredand wear due to abrasion cut to a minimum.

6. In a system for pneumatically conveying finely di vided materials,the combination of a pneumatic conveying conduit, a device for forcing astream of air into one end of the conduit to move finely dividedmaterial there along, an opening in the bottom of said conduit, covermeans for said opening comprising a member shaped to conform to theshape of said conveying conduit whereby a streamlined flow will beachieved past the opening when covered by said member, means for movingsaid member from a first position where it covers said opening to asecond position where it uncovers the opening to permit the granularmaterial to pass therethrough, and means on the side of the openingopposite said one end of the conduit for creating a flow of air opposingthat created by said device whereby the opposing flow of air will stopboth the flow of air from said device and the granular material carriedthereby above the opening and cause the granular material to fallthrough the opening.

7. A system for controlling the flow of granular material and the like,comprising conduit means for receiving said granular material andconducting it for distribution, means forming apertures at spaced pointsalong said conduit means to provide for discharge of the conductedmaterial at said spaced points, a cover member disposed in operativerelation with each aperture for closing said aperture whereby theconducted material is movable past said aperture without substantialpressure drop, actuator means for positioning said cover member betweenopen and closed positions and including motor means for effecting thedisplacement of said cover member, electrical control means includingswitch devices responsive to the position of said cover, and means foreffecting an opposing flow of air to channel the granular materialwithin said conduit through the outlet when it is uncovered by saidcover member and operating responsively to said electrical controlmeans.

8. In a system having a valve for controlling the passage of solidmaterial therein, the structure comprising a conduit, means forming anaperture within said conduit to provide a discharge for the granularmaterial conveyed therein, a cover member having a sealing portionadapted to sealingly engage said conduit and proportioned to cover thedischarge aperture therein to provide uninterrupted passage of materialthrough said conduit, actuator means for positioning said cover betweenopen and closed positions wherein said cover member is in sealingrelation or unsealing relation with the discharge opening in saidconduit, cover-positioning means for disposing said cover in sealingrelation with the discharge opening or retracting it from sealingposition to provide for a discharge of material within said conduit,electrical switching means, means operatively combined with saidcoverpositioning means and adapted to operate said electrical switchingmeans whereby the operation of conveying material through said conduitis coordinated with the operation of said cover member, and means forproducing a pressure in opposition to the conveying pressure to impedethe passage of material beyond said discharge opening and therebyeffecting discharge flow of material comprising a conduit for directinga flow of material therethrough, a discharge valve disposed at each ofthe locations of material outlet and each including means forming anoutlet opening within said conduit, a plurality of cover members each ofwhich is proportioned to seal an associated one of said openings andprovide a substantially unimpeded flow for the materials that continuepast the opening, actuator means for positioning each cover between aclosed discharge opening-sealing position and a second position whereinthe opening is uncovered and material coveyed within said conduit willdischarge through said discharge opening, means for controllablyactuating said cover member between its open and closed positions todivert the flow of material within said conduit or provide its continuedpassage therethrough, and means for opposing the conveying pressurewithin said conduit to direct the material conveyed through said conduitoutwardly through one of said discharge openings which is uncoveredwhile all others openings are covered.

References Cited by the Examiner UNITED STATES PATENTS 2,752,203 6/1956Thayer 302-59 2,753,221 7/1956 Thayer 302-59 2,889,856 6/1959 Magnusonl3781.5

SAMUEL F. COLEMAN, Primary Examiner.

1. IN A SYSTEM FOR PNEUMATICALLY CONVEYING FINELY DIVIDED MATERIALS, THECOMBINATION OF A PNEUMATIC CONVEYING CONDUIT, A DEVICE FOR FORCING ASTREAM OF AIR INTO ONE END OF THE CONDUIT TO MOVE FINELY DIVIDEDMATERIAL THEREALONG, AN OPENING IN THE WALL OF SAID CONDUIT, COVER MEANSFOR SAID OPENING HAVING A FIRST POSITION WHEREIN IT COVERS THE OPENINGAND A SECOND POSITION WHEREIN IT UNCOVERS THE OPENING TO PERMIT GRANULARMATERIAL TO PASS THERETHROUGH, AND MEANS ON THE SIDE OF THE OPENINGOPPOSITE SAID ONE END OF THE CONDUIT FOR CREATING A FLOW OF AIR OPPOSINGTHAT CREATED BY SAID DEVICE WHEREBY THE OPPOSING FLOW OF AIR WILL STOPBOTH THE FLOW OF AIR FROM SAID DEVICE AND THE GRANULAR MATERIAL CARRIEDTHEREBY ADJACENT THE OPENING AND CAUSE THE GRANULAR MATERIAL TO PASSTHROUGH SAID OPENING.